Improvement in millstone-dress



H. GRIGG & W. MOELROY.

MILLSTONE-DRESS. No.183,,664. Patented Oct. 24,1876.

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UNITED STATES PATENT QFFIGE.

HENRY GRIGG AND WILLIAM MGELROY, OF LOGKPOBT, NEW YORK.

IMPROVEMENT IN MILLSTONE-DRESS.

Specification forming part of Letters Patent No. 183,664, dated October 24,1876; application filed September 2, 1876.

To all whom it may concern:

Be it known that we, HENRY GRTGG and WILLIAM MoELRoY, oi Lockport, Niagara county, State of New York, have invented a new and Improved Millstone-Dress, of which the following is a specification:

In the accompanying drawing, Figure 1 is a plan view of our improved millstone-dress; and Fig. 2 is a section of the same, taken on line X X of Fig. 1.

Similar letters of reference indicate corresponding parts.

Our invention consists in beveling the inner portion or bosom of a millstone, from a point about ten inches from the periphery down to the eye,making the space thus formed about one-half inch deep at the eye. It also consists in cutting furrows from the eye outward, on a radial line from the center of the stone, to the line that defines the beveled portion, starting in a line at the eye, and increasing to the required depth at the outer edge of the beveled portion. The grooves, from this point, are tangential to a circle drawn outside of the eye, so that they have an inclination or draft of from five to eight inches.

The object of our invention is to provide a millstone-dr'ess that will increase the quantity of middlings.

In the drawing, A is a millstone, of which Bis the periphery, and C the eye. a. is the beveled portion, which is defined by the line b, and is one-half inch, more or less, in depth at the eye of the stone. D D are grooves or furrows, that start in a line at the eye of the stone, and run radially to the line b, at which point they are of the depth required. From the line b to the periphery of the stone, the

furrows D are cut on a line running tangential to a circle, 0, described concentrically to and outside of the eye 0, so that the pitch or draft of the furrows represented by the arrows at is from five to eight inches. The plane surface E between the furrows is of about one-third the width of the furrows, more or less. Both the upper and lower stone should be dressed in the same manner.

Having thus described our invention, we claim as new and desire to secure by Letters Patent The millstone having the beveled portion at, radial and tangential furrows D, and plane surfaces E, as and for the purpose set forth.

HENRY GRIGG. WILLIAM MOELROY. Witnesses:

J. A. Dnrnss. EDWARD M. GRIGG. 

